A new approach to peptide synthesis is sought through the development of a coordinated set of new protective groups, new amide forming reagents, and reagents for affinity chromatography. The major objectives turn on the development of "safety catch" carboxyl activating functionalities which serve as C-terminal protective groups yet can be converted in high yield when needed into selective and clean acylating species and on the further development of amide forming reagents which, together with the "safety catch" feature, permit intramolecular amide forming reaction and which leave a solubilizing protective group attached to the peptide backbone. The benzisoxazolylmethyleneoxycarbonyl (Bic) and p-dihydroxyboronatobenzyloxycarbonly (Dobz) protective groups for amines are to be tested for their compatibility with commonly used methods for peptide synthesis for thier capacity for selective removal under mild conditions, and in the case of the Dobz group, for the scope and utility of its affinity separability. The initial test is a synthesis of the tetradeca peptide hormone, somatostatin. BIBLIOGRAPHIC REFERENCES: D. Kemp, M. Trangle, and K. Trangle, Anderson Test Assessment of Racemization for the HBT-DCC Peptide Coupling Prodecure, Tetrahedron Lett., 31, 2695 (1974). D. Kemp, S. Choong, and J. Pekaar, Rate Constants for Peptide pNP Ester Coupling Reactions in DMF. A Model for Steric Interactions in the Peptide Forming Transition State, J. Org. Chem., 39, 3341 (1974).